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I'm looking for a keyed disconnect for the main battery cable for a soon to be in my hands 53 M37. I was at the local Carquest and they had a DS-249 listed that specs at 6-36 Volts, 175Amp continuous and 800amp intermittent. Is this rated high enough or can someone recommend something else? I want to go with the keyed switch for shows, etc so that everything on the truck is dead. (I've seen many little kids flipping switches in vehicles like they are playgrounds and don't want dead batteries, fried ignition or crisp kiddies )

Just a warning, once she is in my hands, I'll be back with lots more questions.

If you don't run the main starter cable through it you should be good. Just run everything else through it. Assuming you still have a foot starter, they will be able to crank the motor, but it won't start.

Thanks, but I'd really like to kill all the power, including the starter. Read about a starter having issues a while back (either here or at SS) and it would be good to be able to turn a switch and kill all draw.

Warren. Maybe your looking for something like this ?

http://www.summitracing.com/parts/PRF-30204/?rtype=10

You can use a simple key switch instead of a toggle. The only thing is it operates off of 12 volts..


Sal

The 800 amp intermittent duty is more than adequate for the starters. When checking stall torque, MCS4301 draws 250 amps max at 10 volts at stall and MCZ4002 starter draws 75 amps max at 8 volts at stall. Regular cranking would be a lot less.

Had the same idea and made this from stuff I had on hand like the 24v relay, breaker and switch. It disconnects the ground side of the system and with the drivers seat down the switch is not visible so no little busy hands can play with it and energize it.

http://news.webshots.com/album/559916335djjyqG

I run a manual #50710 - Painless Performance Master Disconnect Switch for everything except the winch (Surge Amp Rating 1,000 amps). It's just not a keyed unit and I've had no problems..

WarrenD wrote:I'm looking for a keyed disconnect for the main battery cable for a soon to be in my hands 53 M37. I was at the local Carquest and they had a DS-249 listed that specs at 6-36 Volts, 175Amp continuous and 800amp intermittent. Is this rated high enough or can someone recommend something else? I want to go with the keyed switch for shows, etc so that everything on the truck is dead. (I've seen many little kids flipping switches in vehicles like they are playgrounds and don't want dead batteries, fried ignition or crisp kiddies )

Just a warning, once she is in my hands, I'll be back with lots more questions.

The switch you listed is plenty sufficient, we have used many over many years, with only 1 issue ever. That one just simply failed within a day or 2, some sort of defect I'm sure as we replaced it and it has run for years now without further issue.

Thank you all for your time to reply. I get a very generous discount through the local Carquest (a fellow employee works there part time and has arranged steep discounts for all where I work). Just want to be sure I'm not creating more problems than I'm solving!
I probably should have added that the coming 53 M37 has a 60amp alternator out of a deuce.

I used a keyed Cole-Hersey out of the JC Witney book. Same ones we use on the Fire Trucks at work. It was cheap and had a high rating (can't recall at moment). Placed it on teh front of the passenger seat riser and used it to break the ground cable. Killed everything in my truck and it worked great since 1996 even using teh 60 amp alternator.
Rick

Thanks, Rick. I got the one you suggested and installed it yesterday. Feel much better about leaving the truck in the garage with the batteries completely disconnected. Install was relatively painless, had to have a custom 2 ga cable made and buy a 3/4" drill bit, but the actual work went well.

A disconnect is crucial in my opinion. I went with Charle's recomendation a few years back. Can't remember the NAPA number but it's a keyed disconnect that is mounted to the front of the passenger's seat. Unhooks the battery negative and was a breeze to install. Another one of those "while your at it" type of jobs I replaced all the battery cables with welding cable. Not too expensive and quite frankly can you put a price on the risk of your baby burning up? Plus it prevents some little punk climbing in and hitting the starter pedal when your not looking.

Dredging up this old topic, has anyone used a Cole-Hersee 2484-19? The specs look good, but the "weather resistant", not "water proof", rating has me concerned. I'm looking for a battery master disconnect switch that is keyed and waterproof.



Cole Hersee - Weather-Resistant Master Disconnect Switch
Details Single Pole battery disconnect, Two Positions: Off-On
UL listed not listed
Rating 6-36V DC; 175A continuous 1000A intermittent 15 sec. On, 5 min. Off
Terminals two 3/8" copper studs
Actuators "Hencol" lock with two keys
Mounting stem brass, 3/4" - 16, 17/32" long, fits panel through 1/4" thick
Case Plated steel
Sealing "O" ring in operating shaft, Gasket-sealed terminal insulator
Installation Through hole - Clearance for 3/4" dia. mounting stem
Contacts Silver

That's an intermittent rated switch. You need a continuous duty switch. Another option is to used a low amperage keyed dash switch and a remote continuous duty sealed relay. In aviation business this would be called a master switch that controls the master relay. These sealed 24 volt relays are easy to find on the aviation parts boards.

This for example: http://www.aircraftspruce.com/catalog/e ... key=107207

And any keyed on/off switch rated at 5 to 10 amps for the dash.

Thanks for the reply and the photos, Wes.

I'm going to hide the keyed portion, so the remote aspect of the relay isn't important, but your suggestion would, of course, still work even if the keyed switch part is not on the dash. I was just hoping for a simpler installation, i.e. a single keyed switch between the battery group and the vehicle ground. As the parts multiply, so does the potential for failure.

That Cole-Hersee switch is rated for 1,000 intermittent amps, which I figured would be more than sufficient for starting, and also for 175 amps continuous, which should be plenty for the load while the truck is running. Or am I missing something in my calculations?